The Brazilian Coronary Disease Cohort

Introduction:

For decades, patients with obstructive coronary disease, specifically with lesions above 70%, have been the subject of numerous randomized studies and meta-analyses concerning the influence of drug treatments, revascularization (surgical or percutaneous), and lifestyle on their prognosis. In this scenario, the investigators already have a reasonable knowledge of the behaviors most appropriate for both avoiding events and alleviating symptoms. However, one particular subgroup consists of patients whose lesions are non-obstructive. In most cases, these are considered lesions of ≤70%. Many individuals presented obstructive lesions that were deemed appropriate for angioplasty within this classification. For example, in the study Defer of 325 patients with indications of ischemia, 44.3% presented FFR (fractional flow reserve) ≤0.75, which suggested significant obstruction, and were submitted to ATC. Thus, the investigators consider the threshold ≤70% inappropriate since it includes many patients with ischemia when assessed by FFR. Therefore, this study has decided to investigate patients with lesions of ≤50% on the supposition that they do not have obstructive lesions. In addition, although coronary disease may follow a stable clinical course, this is not the case with atherosclerotic plaques. These can grow, become complex, stabilize and reinitiate new cycles of growth/destabilization/stabilization or inactivity, in either the presence or absence of evident symptoms. Though aware of this dynamic, studies were performed to "photograph" at a given time subclinical atherosclerotic load and correlate it to the incidence of the events. The indicators most used for evaluating atherosclerotic load have been the presence of extra-cardiac atherosclerosis (carotid ultrasound) and calcification of the coronary arteries. Furthermore, the calcium score has been used for the same purpose in the Brazilian population: but only as a prognostic indicator among carriers of family hypercholesterolemia. However, there are considerable doubts concerning therapeutic interventions in asymptomatic patients with no critical stenosis. Given this gap, chiefly among the Brazilian population, and being an institution with one of the highest volumes of medical care and screening for coronary disease globally, the investigators have all the necessary conditions to put this important public health problem into perspective.

Objectives:

To evaluate clinical evolution, in eight years, of patients with no coronary lesions or lesions <50%, invasive coronary angiography (ICA) exams or coronary angiotomography is performed for the diagnosis of coronary disease.

Population: